Jack Ryan: Shadow Recruit wasn't the first time Keira Knightley auditioned to work with Sir Kenneth Branagh.

"I went for a role in Hamlet [Branagh directed and starred in the 1996 big screen adaptation] when I was 11 and I didn't get it, but he was very lovely," she says, smiling coyly. "But this was the first time we've crossed paths since then."

The knock-back didn't stop Knightley from pursuing her acting career, she's gone on to earn an Oscar nomination for her performance in 2005's Pride & Prejudice, among numerous other plaudits.

Dressed for a day of interviews in a pretty floral frock, Knightley's shivering in the harsh chill of the elegant hotel's air conditioning. Branagh quickly whips off his suit jacket and tucks it over her shoulders.

"The main reason I did this film was Ken Branagh," says the actress. "I've been a huge fan of his since I was a kid and the opportunity to work with him, not only as an actor but a director, was something I couldn't say no to."

In turn, Branagh, who was oblivious to Knightley's early audition until now, reveals he's been closely following her work for years.

"She's very adventurous and I love her in films like A Dangerous Method," says the 53-year-old. "I've been watching her since she made her debut on television [Knightley was six when she got an agent and soon began landing small jobs in adverts and TV] and always wanted to work with her.

"She's the most varied actress and I feel we have so much work to come from her yet."

Based on the novels by Tom Clancy, the Jack Ryan reboot sees Star Trek actor Chris Pine take on the role of the CIA agent previously portrayed on screen by Alec Baldwin, Harrison Ford and Ben Affleck.

Jack is an all-American boy who accidentally stumbles into a life of espionage when recruited as an analyst by a CIA boss (Kevin Costner).

When he spots a Russian company acting suspiciously, Jack's sent to Moscow to investigate - and suddenly finds himself thrown in at the deep end as an active CIA agent.

Having Branagh as both her on-screen sparring partner and at the movie's helm was strange, Knightley admits.

"It was hysterical, totally mad, because he's playing the nastiest villain you can imagine, who does some horrific things to me. So he'd be completely horrendous, screaming in my ear and all the rest of it, and then suddenly go, 'OK ladies and gentlemen, thank you so much. That's a cut and that was lovely', and be this sweet man. So it was quite schizophrenic," she says.

Branagh hadn't always intended to take on the role of Viktor, but as he began working on the project, he found it impossible to resist.

"It was several months into the process and having spent a lot of time with Chris Pine developing the story, the script had developed to the point where the role of Viktor was richer," he explains. "I thought his history was fascinating, and it turned into a part which I thought would be good fun to play."

Smiling mischievously, he adds: "Then I gave myself a ring and said, 'You're playing it, what do you think?' 'Oh OK, I will then!'"

Costner, a fellow actor-director, is an old friend, it transpires.

"It's like coming full circle," reveals Branagh. "When I first went to Hollywood, on tour with two Shakespeare plays, I got a call at the theatre saying a fellow called Kevin Costner would like to take me out to lunch.

"He wanted to ask me what it's like to act and direct in a movie at the same time, because I'd just done it in Henry V, and he was about to do it in Dances With Wolves.

"We had a long boozy lunch sharing war stories. It was the beginning of a friendship that's lasted all that time and, in fact, he was very helpful about the same process 25 years later."

Branagh's now an old hand at directing himself, having doubled up for a number of films, including 1994's Frankenstein. Then in 2011, he took the helm of the adaptation of Marvel comics' Thor.

So what attracted this thespian to the world of action films?

"I always felt as though I started making action films with Henry V, which ends with the Battle of Agincourt, 10, 15 minutes of non-stop fighting," he points out.

"But with most movies, I'm interested in the mainstream. Where there is action, it's usually a sleight of hand."

One very tense scene sees Knightley's character trying to distract Viktor from Jack's absence from the dinner table, by drawing him into a conversation about Russian literature.

Knightley jokingly complains that Branagh made her read the whole of Mikhail Lermontov's novel A Hero Of Our Time in preparation.

In fact, after her starring role in 2012's Anna Karenina, the 28-year-old had been looking to escape the deep, dark world of Russian literature.

"When I finished doing Anna Karenina, I realised that I'd been playing characters that died, or had something horrendous happen to them, for about the last five years, and I fancied doing something fun!" she exclaims.

"I've never done a thriller before, and it's been a genre that I've really liked. I was excited by the challenge."

The break from tragic heroines has given Knightley a taste for lighter projects, it seems.

"It's always nice to have somebody who's intelligent, although I don't know..." she muses. "I don't think I've ever played an unbelievably stupid character, and actually that might be quite interesting.

"I'd be quite interested to play a really, really stupid person!"

Extra time - actors taking their own direction

:: Clint Eastwood - The 83-year-old Western star's been directing himself since the Seventies, with notable films including the Oscar-winning Million Dollar Baby in 2004.

:: George Clooney - The Hollywood hunk first turned director in 2002 and won critical acclaim when he both helmed and starred in 2005's Good Night, And Good Luck.

:: Sylvester Stallone - Sly may be known as an iconic action star, but don't forget he's been writing and directing many of his movies himself since 1978's F.I.S.T. and Paradise Alley.

:: Ben Affleck - Hollywood heart-throb Affleck had started being panned by critics for his acting, but since he turned director for 2007's Gone Baby Gone, they've been queuing up to give him awards, including an Oscar for his most recent effort, Argo.

:: Lena Dunham - There aren't many actresses who also direct, but the 27-year-old star's helping fight the Hollywood glass ceiling, directing herself in award-winning TV series Girls.